How to use elastic search suggester to perform auto complete

elastic-search suggester 

Use kibana sense to create your mappings 
Note:Dont forget to add suggest: filed with your mapping as shown below 

eg:

{
  "mappings": {
    "User": {
      "properties": {
        "fName": {
          "type": "string",
          "index": "not_analyzed"
        },  
         "suggest" : {
           "input": [ "Nevermind", "Nirvana" ],//on these input you will get the suggestions 
           "output": "Nirvana - Nevermind",//this will be your auto complete return result
           "payload" : { "artistId" : 2321 },//you can include the payload too with return resule
           "weight" : 34 //preference 
        }
     }
   }
}

  

Then to use the suggester
you need to do like shown below
On the head object like in this case "music" is parent object which has "songs"
you need to add suggester and point to suggest field

curl -X POST 'localhost:9200/music/_suggest?pretty' -d '{
    "song-suggest" : {
        "text" : "n",
        "completion" : {
            "field" : "suggest"
        }
    }
}'

To add fuzzy suggester
curl -X POST 'localhost:9200/music/_suggest?pretty' -d '{
    "song-suggest" : {
        "text" : "n",
        "completion" : {
            "field" : "suggest",
            "fuzzy" : {
                "fuzziness" : 2
            }
        }
    }
}'

that's it you will get your suggester working

NOTE: this search might  also show you deleted documents .
if you dont want this to happen then you need to index your page every time you add or update the data

As shown below :
$ curl -XPOST 'http://localhost:9200/_optimize?only_expunge_deletes=true'


for more info: https://www.elastic.co/guide/en/elasticsearch/reference/current/search-suggesters-completion.html